A magnitude 6.7 earthquake struck Ecuador's coast early on Wednesday in the same zone where a 7.8 tremor killed more than 650 people last month.

There was no immediate report of damage from the latest quake, which cut electricity in some coastal areas and sent people running into the streets as far away as the highland capital Quito, witnesses said.

"The epicenter was Mompiche. There are no damages reported. There is no tsunami warning," President Rafael Correa tweeted.

The Pacific Tsunami Warning Center also said no Pacific-wide tsunami was expected from the quake, whose depth the U.S. Geographical Survey put at 10 km (6 miles).

The April earthquake, Ecuador's worst in nearly seven decades, flattened buildings along the coast. As well as the fatalities, it also injured around 16,600 people and caused an estimated $2 billion of damage.